Test Quick Guide

Thyroglobulin (Tg) is a protein made past the thyroid gland. Tg can also be produced by certain types of thyroid cancer.

The thyroglobulin test is a type of tumor mark test used to measure out the amount of Tg in the claret. Nearly often, doctors gild Tg testing to evaluate the effectiveness of thyroid cancer handling or to monitor for a recurrence of thyroid cancer afterward handling is completed. Tg levels may likewise be measured to help diagnose certain non-cancerous weather of the thyroid.

About the Test

Purpose of the test

The purpose of a Tg examination is to measure the corporeality of thyroglobulin in the blood. Doctors routinely order thyroglobulin testing to manage patients with a history of papillary or follicular thyroid cancer, two of the most common types of thyroid cancer. Testing may exist performed for several reasons, including:

  • Postoperative evaluation: Tg testing tin can exist used in patients recently treated for thyroid cancer to evaluate whether treatment was constructive in eliminating thyroid cells in the torso. Tg levels measured 6 to 12 weeks after successful surgical treatment should be very low.
  • Monitoring for recurrence: A doctor may order thyroglobulin testing after a patient has completed handling to check if cancer has returned, which is referred to as a recurrence. To monitor for a recurrence, doctors order periodic Tg testing aslope other tests similar a physical exam and imaging tests.
  • Prognosis: Thyroglobulin levels may exist used to gauge survival rates and the likelihood that cancer will return, which is called a patient's prognosis. For this purpose, doctors consider several Tg levels measured over time.

Some doctors may check thyroglobulin levels when diagnosing hyperthyroidism and hypothyroidism, thyroid disorders that are non cancer.

What does the examination measure?

Thyroglobulin tests measure the corporeality of Tg in the blood.

Thyroglobulin is a protein produced by the thyroid gland. The thyroid gland is a small butterfly-shaped organ at the front of the neck and beneath the voice box. The thyroid produces the hormones triiodothyronine (T3) and thyroxine (T4), which play an important role in many body functions, including digestion, fertility, growth, and heart rate.

Earlier being released into the bloodstream, T3 and T4 are stored in the thyroid gland equally thyroglobulin. In good for you people, the thyroid gland releases depression levels of thyroglobulin into the bloodstream along with T3 and T4. Nonetheless, papillary and follicular thyroid cancer also produce thyroglobulin. This means that people with thyroid cancer may have higher thyroglobulin levels than salubrious individuals.

When should I become a thyroglobulin test?

Your doctor may recommend thyroglobulin testing if you are existence treated for thyroid cancer. Recommendations for when you should get tested will depend on why your physician is ordering a Tg test.

If you recently had surgery for thyroid cancer, your physician may mensurate thyroglobulin levels to make up one's mind whether your handling was successful in removing all of your thyroid cells, including both noncancerous and cancerous cells. This postoperative evaluation of Tg levels is usually ordered 4 to 6 weeks post-obit surgery.

Testing is besides performed periodically after treatment to monitor for thyroid cancer recurrence. Testing to measure Tg levels is ordinarily ordered every three to six months during the first yr following handling. After initial handling and follow-up, how often testing is needed varies based on unique features of the cancer and how the cancer responded to the initial handling.

If your dr. is concerned nigh hyperthyroidism or hypothyroidism, they may guild a thyroglobulin exam to diagnose these conditions.

Finding a Thyroglobulin Test

How to get tested

A test to measure thyroglobulin levels must exist ordered by a wellness professional. The sample needed to perform Tg testing is typically taken in a physician's office, medical dispensary, or laboratory.

Can I take the test at dwelling?

At this time, there are no calm examination kits bachelor that measure out thyroglobulin levels. Tg testing must exist ordered by a md and your sample must be sent to a laboratory for analysis.

However, you tin can purchase at-home examination kits that appraise other substances related to thyroid function. More information almost these test kits tin be found on our page virtually calm thyroid testing.

How much does the test cost?

The cost of a thyroglobulin examination varies based on multiple factors including your insurance status, whether other tests are performed at the same time, and where testing is conducted.

When ordered by a doctor, testing is ofttimes covered by health insurance. Information technology is important to talk with your doctor, laboratory, or wellness insurance company about out-of-pocket costs you may exist responsible for including copays and deductibles.

Taking the Thyroglobulin Test

Thyroglobulin testing is performed on a sample of claret. The blood sample is often collected from your arm in a medico'southward office, medical clinic, or laboratory.

Before the exam

Typically, no special exam grooming is needed earlier a Tg exam. If y'all take questions about how to prepare for testing, you can speak with your dr.. It is important to follow any pre-exam instructions provided past your doctor or the laboratory to ensure an authentic result.

During the test

Thyroglobulin tests require a sample of blood fatigued from a vein, often collected from the inside of your elbow. The health professional drawing your blood volition typically place an rubberband band called a tourniquet around your upper arm to increase the amount of claret in your vein. A needle is then inserted into the vein to begin the drove process. Blood will flow through the needle into a test tube or minor vial.

The procedure to draw your blood usually takes a few minutes. You might feel a slight hurting or stinging sensation in your arm where the needle is inserted, just the discomfort should not last long.

After the examination

Once the health professional removes the needle from your vein, they utilise force per unit area and a bandage to the area. This will stop the flow of claret and assist to forestall bruising.

Normally, you lot tin can return to your normal activities post-obit your blood draw. If yous detect continued bleeding, discomfort, or signs of infection at the procedure site, yous should speak with your doc.

Thyroglobulin Examination Results

Receiving test results

Your doctor should have the results of your Tg examination within several business concern days. They may contact you to provide results over the phone or to schedule an engagement to talk more about your examination result and next steps in your intendance.

If you have admission to an electronic medical record, your doctor may upload the results of your test online. Yous may also receive a re-create of your consequence in the mail.

Interpreting examination results

Your test study volition provide information about the level of thyroglobulin detected in the blood in nanograms per milliliter (ng/mL). Your study will also include a reference range used to translate your result. A reference range is the expected range that helps doctors make up one's mind what is considered for a healthy population.

Dissimilar methods can exist used to perform thyroglobulin testing on a blood sample. The examination methods used may vary from laboratory to laboratory. Other factors, such as the type of initial treatment and the presence of anti-thyroglobulin antibodies, can also affect your exam results.

Subsequently successful treatment for thyroid cancer, Tg levels should drib significantly. Elevated levels post-obit treatment can advise that treatment was unsuccessful in removing all thyroid tissue from the body, that thyroid cancer has spread to other areas of the body, or that yous may be experiencing a recurrence of cancer.

Because your doctor is the most familiar with your medical history and current health status, they are in the all-time position to interpret your test result and say what these results mean for your health.

Are test results authentic?

Tests that measure thyroglobulin levels are widely used and are generally considered accurate. All the same, no exam is perfect and several factors tin influence the reliability of your test effect.

Thyroglobulin antibodies, also known as antithyroglobulin (anti-Tg) antibodies, are proteins produced by the immune system that attack healthy thyroid tissue. Thyroglobulin antibodies

bind to Tg. Because Tg testing can't notice Tg that is jump to thyroglobulin antibodies, anti-Tg antibodies can cause your test result to appear depression. Doctors typically order Tg and anti-Tg antibody tests at the aforementioned fourth dimension to account for this and improve the reliability of testing.

Multiple methods are available to perform thyroglobulin testing on a blood sample. The same testing method should be used each time the exam is performed, as there is variability among exam methods. Results from Tg tests taken over time using different methods cannot be straight compared.

Some studies suggest that the dietary supplement biotin may influence thyroglobulin levels, although more than research is needed to ostend this finding. If you take biotin supplements, you may wish to talk to your doc about any possible impact on your Tg examination results. You lot can besides ask your medico whether they recommend having another Tg examination subsequently not taking biotin.

Y'all can talk with your doctor about the reliability and significance of your Tg test result given your state of affairs.

Do I need follow-up tests?

If you accept an elevated thyroglobulin level after treatment for thyroid cancer, additional testing may be suggested depending on your state of affairs. Your doctor may suggest a concrete exam, imaging tests, or a biopsy to learn more.

If you need follow-upwardly testing, your doctor can provide data about the tests that are recommended for your situation and the risks and benefits of each test.

Questions for your md nearly test results

It is normal to have questions most the results of laboratory tests. Your doctor can aid answer questions about your results and what they mean in the context of your overall wellness. Here are some questions you may want to ask your doc virtually thyroglobulin testing:

  • What were my thyroglobulin test results?
  • What does the result of my exam tell you about the status of my thyroid cancer?
  • How frequently will I have testing to measure my thyroglobulin level?
  • Practice y'all recommend other testing based on the results of my Tg test?
  • Do I take anti-thyroglobulin antibodies?

Related Tests

Thyroglobulin examination vs. thyroglobulin antibiotic test

Thyroglobulin tests measure out the Tg poly peptide in the bloodstream. Thyroglobulin antibody tests observe Tg antibodies that are produced by the immune arrangement and tin crusade damage to the thyroid.

Thyroid antibodies tin influence the accurateness of Tg test results, making information technology more difficult to find a cancer recurrence. Doctors society both Tg and TgAb tests when measuring thyroglobulin levels to cheque for thyroid cancer recurrence.

Related Content

View Sources

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